<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <meta http-equiv="X-UA-Compatible" content="ie=edge">
    <title>CSS variables</title>
    <link rel="stylesheet" href="style.css">
</head>
<body>
    <header id="main-header">
        <h1>CSS variables</h1>
    </header>

    <div class="container">
        <div class="grid">
            <div class="box">
                <h1>Hello everyone</h1>
                <p>Lorem ipsum, dolor sit amet consectetur adipisicing elit. Officia consectetur rerum deleniti neque, quasi dolorem perferendis, reprehenderit natus unde id magnam numquam. Ducimus natus quisquam voluptatibus sit impedit sapiente nemo.</p>
            </div>
            <div class="box">
                <h1>Hello everyone</h1>
                <p>Lorem ipsum, dolor sit amet consectetur adipisicing elit. Officia consectetur rerum deleniti neque, quasi dolorem perferendis, reprehenderit natus unde id magnam numquam. Ducimus natus quisquam voluptatibus sit impedit sapiente nemo.</p>
            </div>
        </div>
    </div>
    
    <script>
        const box = document.querySelector('.box')
        const boxStyles = getComputedStyle(box)

        const boxMainColor = boxStyles.getPropertyValue('--box-main-color')
        // box.style.setProperty('--box-main-color', '#fff')
        
    </script>
</body>
</html>